03 - Unified Modeling Language

ucla | CS 130 | 2024-10-07 18:37

Unified Modeling Language (UML)

Unified Modeling Language (UML)

older, more popular framework for designing diagrams
allows for multiple analysis methods

Use Case Diagram

describes system as aa black box, used to model the customer interaction
identifies possible service use cases, actors/interfacers, external system interactions
e.g.
relationships between actors/interactions

Activity Diagram

models control flow and data flow in a use case of the subject system

Class Diagram

describes white boc implementation of a system in terms of types: classes, interfaces, primitives
a type defined by attributes and features/operations
multiple abstraction levels
abstract class - cannot be instantiated in italic
integers on associations depict the possible count of the associated class within the higher up - there may also be “flags” that identify properties of the association NOTE: my descriptions of compositions uses terms source (arrow or empty end) and destination (diamond end); this conflicts with my description of association having source ()
associations are directional - no arrows = bidirectionl, arrows represent that the source has a property of the dest. of the association arrow, but the dest. class has no property of the source class
composition - association with a black diamond end (signifies special deletion semantics) = class by the diamond (destination) is an owner of the source, e.g. account is composed of 1 shopping cart
- important for deletions - items that are composed in another class will be deleted when the destination (black diamond class) is deleted
- deletion is transitive and cascades down composition connections but not association connections, deletion only cascades FROM diamond TO empty i.e., source only deleted if dest deleted in composition
attribute/operation scoping
- - : public; - : private; # : protected
Attribute modifiers/syntax
Operation modifiers/syntax - NOTE: from below i refer to diamond end as source and arrow end as destination
inheritance = source “is-a” dest;
association/composition = source “has-a”